The present invention relates to an apparatus for filtering molten scraps of light metals such as magnesium and aluminum alloys in the industrial scale for regenerating and/or refining the same.
Recently, the amount of the recycled metals such as magnesium and aluminum alloys regenerated from the scraps thereof for the reuse of the same has has been increased year by year and such a recycling of the metals serves greatly for the save of energy and for the supplementation of metallic resources.
Furthermore, the regeneration of used metallic materials such as magnesium and aluminum alloys resulting from the production processes has become important. Such a regeneration of metals is not limited to metals such as magnesium and aluminum alloys but is extended to other metals.
As a process for regeneration, a process has been known as disclosed in U.S. Pat. No. 4,385,931 wherein a layer of flux is formed on the bottom of the processing furnace installed stationarily and molten metal to be regenerated is charged in the processing furnace so that it is passed through the layer of flux thereby permitting the inclusions such as oxides contained in the molten metal to be absorbed and separated.
With the above mentioned process, however, since the production efficiency and the yield are low, this process has not been carried out in the industrial scale. For example, when the metal of magnesium alloy is passed through a flux layer, loss of the metal caused by being carried away by the flux layer is great so that the yield is lowered. On the other hand, the flux is carried into the molten metal passing through the flux layer and, since it is difficult to completely remove the flux from the molten metal, corrosion resisting property of the regenerated metal is lowered by the chlorine contained in the flux. Furthermore, since the stocks stored outdoor or the scraps collected from cities contain oils and a large amount of dusts, the processing of such stocks and scraps is troublesome and the production efficiency becomes low, while much amount of the flux is consumed in the processing. Therefore, the payability becomes remarkably worse and the quality of the regenerated metal is deteriorated.
In consideration of the troubles due to the use of the flux as described above, a process has been proposed for regenerating scraps of metal without using flux. This process is based on the principle to remove impurities by the filtration as disclosed in the Japanese Patent Publication No. 56-18063.
Such a prior art of filtering apparatus is, however, has a low production efficiency and such an apparatus will give rise to various defects in operation in the industrial scale.